WO2014201193A1 - Liant pour batterie hybride à base d'un copolymère d'éthylène-fluoropolymère - Google Patents

Liant pour batterie hybride à base d'un copolymère d'éthylène-fluoropolymère Download PDF

Info

Publication number
WO2014201193A1
WO2014201193A1 PCT/US2014/042026 US2014042026W WO2014201193A1 WO 2014201193 A1 WO2014201193 A1 WO 2014201193A1 US 2014042026 W US2014042026 W US 2014042026W WO 2014201193 A1 WO2014201193 A1 WO 2014201193A1
Authority
WO
WIPO (PCT)
Prior art keywords
ethylene
copolymer
weight
composition
acetate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2014/042026
Other languages
English (en)
Inventor
Chongsoo Lim
Daniel P. FORE
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EIDP Inc
Original Assignee
EI Du Pont de Nemours and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by EI Du Pont de Nemours and Co filed Critical EI Du Pont de Nemours and Co
Publication of WO2014201193A1 publication Critical patent/WO2014201193A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H01M4/622—Binders being polymers
    • H01M4/623—Binders being polymers fluorinated polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
    • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
    • C08L23/04—Homopolymers or copolymers of ethene
    • C08L23/08—Copolymers of ethene
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the invention relates to a binder composition and its use in a secondary battery, such as lithium ion battery.
  • lithium ion batteries Since commercial lithium ion batteries were first developed by Sony in the early 1990s, they have been widely adopted in portable electronics such as laptops, tablets and smartphones due to their high energy density, high working voltages, and excellent flexibilities in shapes and sizes. These properties allow lithium ion batteries to accommodate demanding needs from rapidly evolving electronic devices more readily than conventional secondary batteries. Lithium ion batteries are considered as desirable alternative energy sources in emerging markets such as electrified vehicles and energy storage, which will bring about new opportunities and challenges simultaneously.
  • a lithium ion battery typically comprises four components including a negative electrode (anode), a positive electrode (cathode), an electrolyte and a separator, which work in harmony to interconvert chemical energy into electrical energy reversibly as current flow reverses during charge and discharge processes.
  • electrodes are constructed by applying active material onto a current collector in the presence of a binder that affords cohesion between active materials and their adhesion to the current collector.
  • the binder is commonly combined with carbon black for electrical conductivity.
  • Common active materials for anodes include carbon (graphite) or silicon, and, for cathodes, lithium metal oxides, mixed metal oxides, or metal salts of usually lithium.
  • the current collector for anodes is typically Cu, and for cathodes Al.
  • the electrolyte can be a mixture of organic carbonates containing lithium salts.
  • the organic carbonates can include ethylene carbonate, ethyl methyl carbonate, diethyl carbonate, or combinations thereof.
  • the lithium salts can include LiPF 6 , LiBF 4 , LiAsF 6 , L1CIO 4 , L1CF3SO3, LiN(S0 2 CF 3 ) 2 or combinations thereof.
  • the separator is commonly made from a stretched and thus micro-porous multilayered film of polyethylene, polypropylene or combinations thereof. Widely used binders comprise homopolymers and copolymers of polyvinylidene fluoride (PVDF), which have gained success as binders for cathodes and anodes in lithium ion battery technology.
  • PVDF polyvinylidene fluoride
  • PVDF and copolymers such as a copolymer of vinylidene fluoride and hexafluoropropylene (p(VDF-HFP)) are also used as polymer electrolytes and separators alone or in combination with other materials.
  • PVDF might have suitable properties for lithium ion battery application such as relatively wide redox window for electrochemical stability, high molecular weight for strong adhesion to current collector and robust cohesion between active materials, high polarity to increase compatibility with polar cathode active material, proper viscosity, and commercial availability in high purity.
  • PVDF needs improvement in adhesion, percent active loading, swelling behavior and flexibility.
  • PVDF polyvinyl styrene
  • NMP N-methyl-2-pyrrolidone
  • PVDF's high melting point (around 170 °C) aqueous PVDF binders may not go through film forming process effectively in the existing LIB process. Also, additives for the emulsions or dispersions such as surfactants and rheology modifiers can interfere with lithium ion battery action. Although NMP is used as a typical solvent for PVDF, it might need to be deselected at a certain point due to its toxicity. These drawbacks of PVDF can be magnified depending on specific applications.
  • Japanese patent application JP2012-109143 discloses electrochemical cells including a binder comprising a fluororesin aqueous dispersion and water-soluble polyamideimide resin.
  • WO2013008564 discloses a polymeric blend for cathode binder that has multimodal particle size distribution measured by dynamic light scattering. At least one of the polymeric particles contains fluoropolymers such as PVDF, P(HFP-VDF), PTFE or combinations of fluoropolymers blended with polyacrylic acids.
  • fluoropolymers such as PVDF, P(HFP-VDF), PTFE or combinations of fluoropolymers blended with polyacrylic acids.
  • the cathode made therefrom was reported to show high ion conductivity, good oxidation stability, good cohesion between active material and good adhesion to the current collector.
  • JP 2012-238488 describes a polymeric blend of acrylic polymer and PVA having an excellent resistance toward electrolyte solutions.
  • JP 2012-234707 discloses polymeric mixtures of acid-modified polyolefms and dimer acid-based polyamides that show excellent adhesiveness and flexibility.
  • WO2012082991 and US Patent 6,723,785 disclose a process for making an aqueous dispersion of nonaqueous soluble material by using an organic solvent and a water-soluble polymer as a dispersant during the milling process.
  • This invention provides a blend composition
  • a blend composition comprising
  • a halogenated (co)polymer such as polyvinyl chloride, polyvinylidene chloride, polytetrafluoroethylene, polyvinylidene fluoride (PVDF), tetrafluoroethylene- hexafluoropropylene copolymers, vinylidene fluoride-hexafluoropropylene copolymers (PVDF-HFP), vinylidene fluoride-tetrafluoroethylene copolymers, tetrafluoroethylene-hexafluoropropylene -vinylidene fluoride terpolymers (THV), tetrafluoroethylene-hexafluoropropylene-vinyl fluoride terpolymers, tetrafluoroethylene-hexafluoropropylene-vinylfluoride terpolymers, vinylidene fluoride-chlorotrifluoroethylene copolymers, ethylene-chlorotriflu
  • the invention also provides a method for preparing the blend composition above comprising
  • PVDF polyvinylidene fluoride
  • PVDF-HFP vinylidene fluoride-hexafluoropropylene copolymers
  • THV tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride terpolymers
  • THV tetrafluoroethylene-hexafluoropropylene -vinyl fluoride terpolymers
  • tetrafluoroethylene-hexaf uoropropylene-vinylfluoride terpolymers vinylidene f uoride-chlorotrifluoroethylene copolymers, ethylene-chlorofluoroethylene copolymers, polyvinyl fluoride (PVF), perfluoroalkoxy poly
  • the method may further comprise mixing the blend composition with a metal oxide, mixed metal oxide, metal phosphate, metal salt, or combinations of two or more thereof, and optionally an electrical conductivity aid.
  • the composition is useful as a binder composition for use in electrochemical cells such as lithium ion batteries. Accordingly, the invention also provides an electrochemical cell comprising the composition.
  • the electrochemical cell may also comprise a negative electrode (anode), a positive electrode (cathode), an electrolyte and a separator.
  • the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion.
  • a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
  • “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
  • the terms “a” and “an” include the concepts of "at least one" and “one or more than one”.
  • copolymer refers to polymers comprising copolymerized units resulting from copolymerization of two or more comonomers and may be described with reference to its constituent comonomers and/or to the amounts of its constituent comonomers such as, for example "a copolymer comprising ethylene and 15 weight % of methyl acrylate".
  • a description of a copolymer with reference to its constituent comonomers or to the amounts of its constituent comonomers means that the copolymer contains copolymerized units (in the specified amounts when specified) of the specified comonomers.
  • Ethylene copolymers can be melt or solution blended with high performance polymers such as fluoropolymers like PVDF, which can be designed to form IPNs
  • hybrid means either an IPN or polymeric blend made of two or more kinds of polymeric resins and compositions thereof.
  • at least one polymeric component is chemically connected either from its monomer or oligomers to build its polymeric network through other polymeric component.
  • the IPN will form somewhat better mixed polymeric mixtures compared to conventional polymeric blends.
  • the binder system with higher peel strength may make it possible to design a higher energy density lithium ion battery by reducing binder volume contents and increasing cathode active material loading in the unit space of the cathode structure in the lithium ion battery.
  • Improved flexibility in the electrode will bring about improved processability in folding and assembly of lithium ion battery, which can eventually increase freedom in shapes and structural flexibility.
  • the ethylene copolymers that form hybrids with PVDF are completely soluble in the typical electrolyte solvent such as Novolyte ® 1M LiPF 6 70-30 EMC-EC simply standing for overnight. Surprisingly, they withstand dissolution in the electrolytes after they form hybrids with PVDF, showing only slightly increased swell index compared to the pure PVDF system. This remarkable behavior still holds even without any dependence on the presence of curing agent or crosslinking in the hybrid system.
  • the hybrid binder approach can compensate for drawbacks of the individual components.
  • the hybrids of fluoropolymers such as PVDF and ethylene copolymer in various compositions can be easily made by solution or extrusion blending, and can be slightly cured by several curing methods.
  • the ethylene copolymer and PVDF can be crosslinked by diamine curing, which potentially can improve adhesion strength of PVDF and also reduce its stiffness while increasing the molecular weights.
  • This chemically bonded PVDF/ethylene copolymer hybrid may be readily processable in existing lithium ion battery processes, since all resin systems can be applied in the form of either dispersions or NMP solutions.
  • the ethylene copolymer may be selected to maintain excellent chain mobility at the normal drying temperature of LIB processes, which will provide a somewhat better environment for PVDF to extend its polymer chains inside the electrode coating to form a solid binder network.
  • This could solve the problems of existing aqueous binder systems of PVDF and/or PTFE where the binder resin melts at a temperature higher than typical drying temperature of lithium ion battery process.
  • the melting point of PVDF homopolymer is about 170 °C, higher than a lithium ion battery's drying temperature of 100 to 140 °C.
  • emulsified or dispersed particles of PVDF might not flow properly to function as a binder, which may lead to poor film forming, weak binding of active material, poor adhesion to the current collector and ultimately unacceptable lithium ion battery performance.
  • an ethylene copolymer that has melting point from about 70 to about 120°C is blended with the PVDF, the PVDF particles will have a better local environment to extend their polymeric chains because the melted ethylene copolymer will have lower viscosity and be in an amorphous form that can act as a solvent at those temperatures.
  • hybrid binder resins can be dispersed in aqueous media by methods widely used in related arts. First, the binder or its blended mixture is to be dissolved in suitable solvent or mixed solvents. Then, the binder organic solution can be dispersed in aqueous media in the presence of surfactants especially polymeric surfactants.
  • the ethylene copolymer component of the binder compositions can be a dipolymer, a terpolymer, a tetrapolymer, or combinations thereof.
  • the ethylene copolymer may be a copolymer comprising copolymerized units of ethylene and a comonomer selected from the group consisting of an ⁇ , ⁇ -unsaturated monocarboxylic acid or its derivative, an
  • ⁇ , ⁇ -unsaturated dicarboxylic acid or its derivative an epoxide-containing monomer, a vinyl ester, or combinations of two or more thereof.
  • it may be a copolymer having copolymerized units of ethylene and a comonomer selected from vinyl esters and
  • ⁇ , ⁇ -unsaturated monocarboxylic acid esters wherein the polymer contains copolymerized units of at least 2 weight % of the comonomer.
  • at least one comonomer in the copolymer is vinyl acetate, an alkyl acrylate and/or an alkyl methacrylate.
  • the percentage of copolymerized vinyl acetate units can vary broadly from 2 percent to as much as 40 weight % of the total weight of the copolymer or even higher.
  • the weight percentage of copolymerized vinyl acetate units in the copolymer will preferably be from 2 to 40 weight %, especially from 10 to 40 weight %.
  • the ethylene/vinyl acetate copolymer preferably has a melt flow rate, measured in accordance with ASTM
  • D-1238 at 190°C with 2.16 kg mass, of from 0.1 to 40 g/10 minutes, and preferably from 0.3 to 30 g/10 minutes.
  • the ethylene-containing copolymers useful in the compositions described herein can be modified by methods well known in the art, including chemical reaction by grafting with an unsaturated carboxylic acid or its derivatives, such as maleic anhydride or maleic acid.
  • a mixture of two or more different ethylene/vinyl acetate copolymers can be used in place of a single copolymer as long as the average values for the weight percentage of vinyl acetate comonomer units, based on the total weight of the copolymers, is within the range indicated above. Particularly useful properties may be obtained when two or more properly selected ethylene/vinyl acetate copolymers are used in the binder compositions.
  • the ethylene copolymer component may also be an ethylene/alkyl (meth)acrylate copolymer.
  • alkyl (meth)acrylate means alkyl acrylate or alkyl methacrylate or a combination thereof and "ethylene/alkyl (meth)acrylate copolymer” means a thermoplastic copolymer derived from the copolymerization of ethylene and at least one alkyl acrylate or alkyl methacrylate comonomer or a combination thereof, wherein the alkyl group contains from 1 to 8 carbon atoms.
  • alkyl acrylates suitable for use include, without limitation, methyl acrylate, ethyl acrylate and butyl acrylate and examples of alkyl methacrylates include methyl methacrylate, ethyl methacrylate and butyl methacrylate.
  • the relative amount of the alkyl (meth)acrylate comonomer incorporated as copolymerized units into the ethylene/alkyl (meth)acrylate copolymer can vary broadly from a few weight percent to as much as 45 weight %, based on the weight of the copolymer or even higher.
  • the alkyl group in the alkyl (meth)acrylate comonomer used to prepare the ethylene copolymer can be from one to 4 carbon atoms.
  • the level of copolymerized units of alkyl (meth)acrylate comonomer in the ethylene/alkyl (meth)acrylate copolymer is within the range from 5 to 45 weight percent, preferably from 5 to 35 weight %, from 5 to 30, still more preferably from 9 to 28 weight % or 10 to 27 weight % of the total ethylene/(meth)acrylate copolymer, based on the weight of the copolymer.
  • Methyl acrylate (the most polar alkyl acrylate comonomer) can be used to prepare an ethylene/methyl acrylate dipolymer.
  • the methyl acrylate comonomer can be present in a concentration range of from 5 to 30, 9 to 25, or 9 to 24 weight %, of the ethylene copolymer.
  • the ethylene/(meth)acrylate copolymer preferably has a melt flow rate, measured in accordance with ASTM D-1238 at 190°C with 2.16 kg. mass, from 0.1 to 40 g/10 minutes, and preferably from 0.3 to 30 g/10 minutes.
  • ethylene/alkyl(meth)acrylate copolymers may also be used, so long as the level of copolymerized units of (meth)acrylate is within the above-described range, based on the total weight of copolymer present.
  • a mixture of two or more ethylene copolymers can be used as component (a) in the compositions in place of a single copolymer.
  • Particularly useful properties may be obtained when two properly selected ethylene/alkyl acrylate copolymers are used in blends.
  • compositions include those wherein the ethylene/alkyl acrylate component comprises two different ethylene/methyl acrylate copolymers.
  • one may replace a single EMA grade in a blend with an equal amount of a properly selected mixture of two EMA grades, where the mixture has the same weight percent methyl acrylate content and melt index as the single EMA grade replaced.
  • Ethylene copolymers suitable for use herein can be produced by any process, including processes that involve use of a tubular reactor or an autoclave. Copolymerization processes conducted in an autoclave may be continuous or batch processes. In one such process, disclosed in general in U.S. Patent Number 5,028,674, ethylene, the alkyl acrylate, and optionally a solvent such as methanol and/or a telogen such as propane to control the molecular weight, are fed continuously into a stirred autoclave such as the type disclosed in U.S. Patent Number 2,897,183, together with an initiator. Ethylene/alkyl acrylate
  • copolymers produced using an autoclave process can be obtained commercially, for example from Exxon/Mobil Corp, and/or from Elf AtoChem North America, Inc.
  • tubular reactor copolymerization technique will produce a copolymer having a greater relative degree of heterogeneity along the polymer backbone (a more blocky distribution of comonomers), will tend to reduce the presence of long chain branching and will produce a copolymer characterized by a higher melting point than one produced at the same comonomer ratio in a high pressure stirred autoclave reactor.
  • Tubular reactor produced ethylene/(meth)acrylate copolymers of this nature are commercially available from E. I. du Pont de Nemours and Company (DuPont), Wilmington, Delaware under the Elvaloy ® AC tradename.
  • the ethylene copolymer may also include at least one comonomer such as an epoxide-containing monomer or an ⁇ , ⁇ -unsaturated dicarboxylic acid or its derivative.
  • An epoxide-containing monomer can include glycidyl methacrylate, glycidyl acrylate, or combinations thereof.
  • An example is an ethylene glycidyl methacrylate copolymer.
  • An ⁇ , ⁇ -unsaturated dicarboxylic acid or its derivative can include maleic acid, fumaric acid, itaconic acid, a C 1 -C 4 alkyl monoester of maleic acid, a C 1 -C 4 alkyl monoester of fumaric acid, a C 1 -C 4 alkyl monoester of itaconic acid, acid anhydride, or combinations of two or more thereof.
  • An example is a copolymer comprising copolymerized units of ethylene and monoethyl maleic acid ester.
  • Terpolymers or higher order copolymers may also be used.
  • ethylene, vinyl ester or an ⁇ , ⁇ -unsaturated ester and maleic anhydride, glycidyl methacrylate or carbon monoxide can be copolymerized to form terpolymers such as ethylene/methyl acrylate/maleic anhydride, ethylene/butyl acrylate/glycidyl methacrylate (EBAGMA), ethylene/butyl acrylate/carbon monoxide (EBACO) or ethylene/vinyl acetate/carbon monoxide (EVACO).
  • EBAGMA ethylene/methyl acrylate/maleic anhydride
  • EBACO ethylene/butyl acrylate/carbon monoxide
  • EVACO ethylene/vinyl acetate/carbon monoxide
  • the ethylene copolymer is an ethylene methyl acrylate dipolymer, ethylene ethyl acrylate dipolymer, ethylene butyl acrylate dipolymer, ethylene methyl acrylate glycidyl methacrylate terpolymer, ethylene butyl acrylate glycidyl methacrylate terpolymer, or combinations of two or more thereof.
  • Ethylene copolymers with higher alkyl acrylate content, for example, greater than 45 weight % are elastomeric.
  • elastomeric copolymers include a copolymer derived from copolymerization of
  • the copolymer may contain monoalkyl esters of 1 ,4-butene-dioic acid moieties that function as cure sites at a loading from 0.5 to 7 weight percent of the total copolymer (more preferably from 1 to 6 weight % and still more preferably from 2 to 5 weight %).
  • a preferred copolymer is derived from copolymerization of from 15 to 50 weight % of ethylene; from 50 to 80 weight % of an alkyl acrylate; and from 2 to 5 weight % of a monoalkyl ester of 1 ,4-butene-dioic acid.
  • the alkyl acrylate has from 1 to 8 carbon atoms in the alkyl group, preferably from 1 to 4 carbon atoms.
  • a mixture of alkyl acrylates may be used.
  • a first alkyl acrylate is either methyl acrylate or ethyl acrylate and the second (and different) alkyl acrylate has from 4 to 8 carbon atoms, such as butyl acrylate.
  • the total acrylate content comprises from 50 to 75 weight percent of the copolymer (more preferably from 50 to 70 weight %).
  • the elastomeric copolymers may have number average molecular weight from 40,000 to 65,000 and melt indices from 1 to 6 g/10 minutes.
  • the composition includes random copolymers comprising ethylene and at least one alkyl acrylate, with or without an acid cure site.
  • the alkyl acrylates have up to 8 carbon atoms in the pendent alkyl chains, which can be branched or unbranched.
  • the alkyl groups may be selected from methyl, ethyl, n-butyl, z ' so-butyl, hexyl, 2-ethylhexyl, n-octyl, z ' so-octyl, and other alkyl groups.
  • the alkyl acrylates used in the preparation of the copolymers may be selected from methyl acrylate, ethyl acrylate, n-butyl acrylate, z ' so-butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, z ' so-octyl acrylate, and other alkyl acrylates containing up to 8 carbon atoms in the alkyl groups.
  • methyl acrylate or ethyl acrylate is used as the first alkyl acrylate and the second alkyl acrylate has from 2 to 8, more preferably 4 to 8, carbon atoms in the alkyl group (when ethyl acrylate is used as the first alkyl acrylate, the second alkyl acrylate has from 3 to 8, more preferably from 4 to 8, carbon atoms in the alkyl group).
  • alkyl acrylates include combinations of methyl acrylate and a second alkyl acrylate selected from the group consisting of ethyl acrylate, n-butyl acrylate, z ' so-butyl acrylate, 2-ethylhexyl acrylate, and n-octyl acrylate.
  • Methyl acrylate with n-butyl acrylate and methyl acrylate with 2-ethylhexyl acrylate are preferred combinations.
  • alkyl methacrylate comonomer can be used in addition to the alkyl acrylate.
  • an alkyl methacrylate can be used to substitute for the second alkyl acrylate.
  • the copolymer may contain no cure site component, or higher copolymers may contain 1 ,4-butene-dioic acid moieties and anhydrides and monoalkyl esters thereof that function as acid cure sites.
  • acid cure sites that comprise from 0.5 to 7 weight %, preferably from 1 to 6 weight %, more preferably from 2 to 5 weight %, of a monoalkyl ester of 1 ,4-butene-dioic acid, in which the alkyl group of the ester has from 1 to 6 carbon atoms, in the final copolymer.
  • the 1 ,4-butene-dioic acid and esters thereof exist in either cis or trans form prior to copolymerization, i.e. maleic or fumeric acid.
  • Monoalkyl esters of either are satisfactory.
  • Methyl hydrogen maleate, ethyl hydrogen maleate (EHM), and propyl hydrogen maleate are particularly satisfactory; most preferably EHM is to be employed.
  • ethylene represents essentially the remainder of the copolymer relative to the required alkyl acrylates and the optional monoalkyl ester of 1 ,4-butene-dioic acid; i.e., polymerized ethylene is present in the copolymers in a complementary amount.
  • copolymers examples include copolymers of ethylene (E) and methyl acrylate
  • MA copolymers of ethylene (E), methyl acrylate (MA) and ethyl hydrogen maleate (EHM) (E/M A/nB A/EHM) .
  • Copolymers with or without acid cure sites can be readily prepared by copolymerizing ethylene and alkyl acrylate(s) in the presence of a free-radical polymerization initiator including for example peroxygen compounds or azo compounds.
  • a free-radical polymerization initiator including for example peroxygen compounds or azo compounds.
  • Elastomeric ethylene alkyl acrylate copolymers of this type are commercially available under the Vamac ® tradename from DuPont.
  • the second component of the blend composition may be a halogenated (co)polymer, preferably a fluorinated (co)polymer.
  • (co)polymers are those (co)polymers comprising, in copolymerized form, at least one
  • (co)monomer having at least one halogen atom or at least one fluorine atom per molecule, preferably at least two halogen atoms or at least two fluorine atoms per molecule.
  • halogenated polymers include polyvinyl chloride, polyvinylidene chloride, polytetraf uoroethylene, polyvinylidene fluoride (PVDF), tetrafluoroethylene- hexafluoropropylene copolymers, vinylidene fluoride-hexafluoropropylene copolymers (PVDF-HFP), vinylidene fluoride-tetrafluoroethylene copolymers, tetraf uoroethylene- hexafluoropropylene -vinylidene fluoride terpolymers (THV), tetraf uoroethylene- hexafluoropropylene -vinyl fluoride terpolymers, tetrafluoroethylene-hexaf uoropropylene- vinylfluoride terpolymers, vinylidene fluoride-chlorotrifluoroethylene copolymers, ethylene- chlorofluoroethylene
  • Notable fiuoropolymers include polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), perfiuoroalkoxy polymer resin (PFA), fiuorinated ethylene propylene (FEP), poly(ethylene-co-tetrafiuoroethylene) (ETFE), tetrafluoroethylene-hexafiuoropropylene- vinylidene fluoride terpolymer (THV), tetrafiuoroethylene-hexafluoropropylene-vinyl fluoride terpolymer, vinylidene fluoride-hexafiuoropropylene copolymer (PVDF-HFP), polytetrafluoroethylene (PTFE) or vinylidene fiuoride-tetrafiuoroethylene copolymer.
  • PVDF polyvinylidene fluoride
  • PVF polyvinyl fluoride
  • PFA perfiuoroal
  • Polyvinylidene fluoride is of particular note.
  • the functions of a binder in an electrode of lithium ion battery can involve adhesion to the current collector and cohesion between active materials, which are known to be dependent on molecular weight of the binder.
  • the compositions described herein provide improved adhesion over previous binder materials.
  • binder comprising a copolymer derived from copolymerization of (a) from 13 to 50 weight % of ethylene;
  • multifunctional additives with an ethylene copolymer to build up its molecular weight, which can be readily achieved in existing lithium ion battery drying and annealing processes.
  • multifunctional additives can include trimethylolpropane triglycidyl ether, epoxidized soybean oil, epoxidized linseed oil, m- phenylene diamine, 4,4'-methylenedianiline, hexamethylene diamine,
  • Preferred additives include diamine, diepoxide, dianhydride, carbodiimide, isocyanide, polyamine, polyepoxide or polyanhydride types.
  • the ethylene copolymer When the ethylene copolymer contains acid cure sites, it can be crosslinked by forming covalent bonds. Crosslinking involves curing the compounded composition, often at elevated temperature, for sufficient time to crosslink the copolymer.
  • crosslinking is sometimes used to describe this process but vulcanization suggests that heat is required, so “crosslinking” is used herein.
  • acid-containing copolymers disclosed herein the crosslinking process can be conducted over a broad temperature range of 0 to 160 °C. Ambient temperatures of 20 to 25 °C can be used, but optionally heat may be applied to facilitate curing.
  • a blend of the un-crosslinked ethylene copolymer and a curing agent, halogenated polymer, optionally including fillers, other additives and/or other polymers can be subject to a curing step at sufficient time and temperature, such as at 90 to 160 °C and for a time of 3 to 10 hours or longer, to achieve covalent chemical bonding (i.e., crosslinking). Additional curing and annealing can be done during a lithium ion battery's typical annealing process.
  • a crosslinked ethylene copolymer may start to be formed and cured using known procedures at 90°C to 140°C for 60 minutes. Post-cure/annealing heating may be conducted at 90°C to 120°C for several hours.
  • Fillers and additives may include metal oxides, mixed metal oxides, metal phosphates, metal salts, or combinations of two or more thereof, and optionally an electrical conductivity aids as described below.
  • Useful curing or crosslinking agents include diamines or multifunctional amines.
  • the amine function can include at least one primary amine, secondary amine, tertiary amine, polyamine, or combinations of two or more thereof.
  • An example of a small diamine that may be used is hexamethylene diamine. Amino compounds that aggregate in situ thereby providing polyamine functionality can be used. Oligomeric polyamines and other organic molecules containing more than one amine group can also be used. An oligomeric polyamine can have a high molecular weight and may include 2 to 100 amine groups. In applications where extraction or other loss of a small diamine could occur, the high molecular weight polyamine remains to crosslink the acidic copolymer.
  • the binder compositions may contain from 1 to 80 weight % of ethylene copolymer, preferably from 5 to 80 weight %, more preferably from 15 to 40 weight % of the
  • Notable compositions include those with 25 to 75 weight % of ethylene copolymer, based on the combination of (a) and (b).
  • an ethylene copolymer or a crosslinked ethylene copolymer can be combined with a single solvent or at least two component solvents, one of which would be relatively nonpolar and the other would be relatively polar in order to form a stable solution and/or concentrate.
  • nonpolar solvents for this application may have fairly low dielectric constant to break down
  • nonpolar solvents examples include diethyl ether, pentane, cyclopentane, hexane, benzene, heptane, cyclohexane, dimethyl cyclohexane, heptane, toluene, octane, ethyl benzene, xylene, 1 ,4-dioxane, nonane, decane, tetrahydronaphthalene, dodecane and decaline.
  • Relatively polar solvents may be used to accommodate relatively more polar polymeric materials.
  • Useful polar solvents include acetone, methyl ethyl ketone, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, hexyl acetate, methyl propionate, butyric acid methyl ester, propylene carbonate,
  • ⁇ -butyrolactone cyclohexyl acetate, 2-methoxyethyl acetate, ethylene glycol methyl ether acetate, 2-ethoxyethanol acetate, 2-butoxyethanol acetate, diethylene glycol monomethyl ether acetate, propylene glycol methyl ether acetate, ethyl acetoacetate, N-methyl-2- pyrrolidone, ⁇ , ⁇ -dimethyl formamide, ⁇ , ⁇ -diethyl formamide, N, N-dimethyl acetamide, ⁇ , ⁇ -diethyl acetamide.
  • Notable solvents include ethyl acetate and N-methyl-2 -pyrrolidone.
  • a typical method to make binder solutions or concentrates is to place a pellet, granular or powder form of the ethylene copolymer resin in a single solvent or mixed solvent of nonpolar and polar solvents as described above.
  • the ratio of nonpolar solvent to polar one may be from 40:60 to 90: 10, preferably from 40:60 to 80:20.
  • the weight percent of polymer in the solution can be from 0.01 weight % to 40 weight %, typically from 5 weight % to 15 weight %.
  • Mechanical stirring or homogenizing is recommended to fully disperse the binder at room temperature or typically under elevated temperatures of 40 to 100 °C. Heating of the binder solution above 100 °C is discouraged due to thermal sensitivity of some functional groups on ethylene copolymer.
  • halogenated polymers such as polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), perfluoroalkoxy polymer resin (PFA), fluorinated ethylene propylene (FEP), poly(ethylene-co-tetrafluoroethylene) (ETFE), tetrafluoroethylene-hexafluoropropylene- vinylidene fluoride terpolymer (THV), tetrafluoroethylene-hexafluoropropylene-vinyl fluoride terpolymer, vinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polytetrafluoroethylene (PTFE) or vinylidene fluoride -tetrafluoroethylene copolymer in organic solvents can be prepared similarly.
  • PVDF polyvinylidene fluoride
  • PVF polyvinyl fluoride
  • PFA perfluoroalkoxy polymer resin
  • ethylene copolymers a halogenated (co)polymer such as PVDF, PVF, PFA, FEP, ETFE, THV, PVDF-HFP, PTFE or other similar polymers
  • a halogenated (co)polymer such as PVDF, PVF, PFA, FEP, ETFE, THV, PVDF-HFP, PTFE or other similar polymers
  • a method for preparing the blend composition may comprise
  • the resin or resin mixture solution may be converted into an aqueous dispersion by techniques known to related arts by adding the organic solutions into surfactant-containing aqueous media with proper means of mixing.
  • the solvent used in dissolving the resins can be removed by distillation or filtered through a micromembrane. However, sometimes the solvent can be retained. The amount of solvent can be adjusted such that the resulting slurry composition has a viscosity suitable for binding the binder composite to a cathode active material, or an
  • binders include an ethylene (meth)acrylic acid copolymer, a lithium neutralized ethylene (meth)acrylic acid copolymer, a cellulose polymer, a polyacrylonitrile or polymethacrylonitrile.
  • the preferred weight percent of hybrid mixture of the ethylene copolymer and fluoropolymer in the solution/dispersion can be from 0.01 weight % to 40 weight %, typically from 1 weight % to 25 weight %.
  • the binder blends can be prepared by conventional coextrusion of each component resin that may or may not include partial reactions during the mixing.
  • the method for preparing a battery binder composition may further comprise mixing the blend composition with a metal oxide, mixed metal oxide, metal phosphate, metal salt, or combinations of two or more thereof, and optionally an electrical conductivity aid.
  • An electrode can comprise a metal oxide, mixed metal oxide, metal phosphate, metal salt, or combinations of two or more thereof and a binder composition wherein the binder composition can be as described above.
  • the blend composition may further comprise a metal oxide, mixed metal oxide, metal phosphate, metal salt, or combinations of two or more thereof, and optionally an electrical conductivity aid.
  • the cathode active material in the slurry composition can be any one known to one skilled in the art.
  • Suitable cathode materials for a lithium ion battery include without limitation lithiated transition metal oxides such as LiCo0 2 , LiNi0 2 , LiMn 2 0 4 , or L1V 3 O 8 ; oxides of layered structure such as LiNi x Mn y Co z 0 2 where x+y+z is 1, LiCoo. 2 Nio. 2 0 2 , Lii +z Nii_ x _yCo x Aly0 2 where 0 ⁇ x ⁇ 0.3, 0 ⁇ y ⁇ 0.1, 0 ⁇ z ⁇ 0.06; high voltage spinels such as
  • Non-lithium metal compounds can include transition metal sulfides such as TiS 2 , T1S 3 , M0S 3 and transition metal oxides such as Mn0 2 , Cu 2 V 2 0 3 , amorphous V 2 OP 2 0 5 , M0O3, V 2 0 5 , and V 6 0i 3 .
  • the anode active material in the slurry composition can be any one known to one skilled in the art.
  • Anode active materials can include without limitation carbon materials such as carbon, activated carbon, graphite, natural graphite, mesophase carbon microbeads; lithium alloys and materials which alloy with lithium such as lithium-aluminum alloys, lithium-lead alloys, lithium-silicon alloy, lithium-tin alloy, lithium-antimony alloy and the like; carbon materials such as graphite and mesocarbon microbeads (MCMB); metal oxides such as Sn0 2 , SnO and Ti0 2 ; and lithium titanates such as Li 4 TisOi 2 and LiTi 2 0 4 .
  • the anode active material is lithium titanate or graphite.
  • Electrical conductivity aids may be also added to the slurry to reduce the resistance and increase the capacity of the resulting electrode. Suitable conductivity aids include without limitation acetylene black, furnace black, carbon fibers and nanotubes.
  • a cathode active material or the anode active material can be combined with the slurry by any means known to one skilled in the art.
  • the cathode active material or anode active material can be present in the binder composite from 0.1 to 80, 0.5 to 70, or 1 to 60 weight % of the total final composition.
  • the slurry composition comprising the ethylene copolymer and fluoropolymer or the electrode composition comprising the slurry composition and the cathode active material (or anode active material) can be mixed by any means known to one skilled in the art such as, for example, using a ball mill, sand mill, an ultrasonic disperser, a homogenizer, or a planetary mixer.
  • the composition is useful as a binder composition for use in electrochemical cells such as lithium ion batteries. Accordingly, the invention also provides an electrochemical cell comprising the composition.
  • the electrochemical cell may also comprise a negative electrode (anode), a positive electrode (cathode), an electrolyte and a separator.
  • Other components of a battery may include a current collector.
  • An electrochemical cell, battery or lithium ion battery can be produced by any means known to one skilled in the art.
  • Materials for the anode and cathode may include the compositions described above.
  • Any current collector known to one skilled in the art can be used.
  • metals such as iron, copper, aluminum, nickel, and stainless steel can be used.
  • a slurry composition containing the cathode active material or the anode active material disclosed above can be applied or combined onto a current collector followed by drying the slurry and bonding the resultant electrode layer comprising the binder cathode active material or anode active material. Drying can be carried out by any means known to one skilled in the art such as drying with warm or hot air, vacuum drying, infrared drying, or dried with electron beams.
  • the final dry binder layer can be in the range of 0.0001 to 6 mm, 0.001 to 5 mm, or 0.005 to 2 mm.
  • Applying a slurry onto a current collector can be carried out by any means known to one skilled in the art such as, for example, using doctor blade, dipping, reverse roll, direct roll, gravure, or brush-painting.
  • An electrolyte may be in a gel or liquid form if the electrolyte is an electrolyte that can be used in a lithium ion battery.
  • a representative electrolyte is a mixture of ethyl methyl carbonate and ethylene carbonate, typically comprising a lithium salt dissolved in solvent.
  • Known salts include LiC10 4 , LiBF 4 , LiPF 6 , LiCF 3 C0 2 , LiB(C 2 0 4 ) 2 , LiN(S0 2 CF 3 ) 2 LiAsF 6 , or LiSbFg.
  • NMC Lithium Nickel Manganese Cobalt Oxide having a nominal formula of Lii.osNio. 33 Mn o. 33 Coo. 33 0 2 , commercially available under the code NM-1101 from Toda America, Battle Creek, MI, Lot 7711206.
  • Carbon black Super C65, commercially available from Timcal, Westlake, OH, Batch 555.
  • ECP-1 an ethylene copolymer containing 63 weight % of methyl acrylate and 4.7 weight % of ethyl hydrogen maleate, the remainder ethylene, used as 10 weight% solution in NMP.
  • ECP-2 an ethylene copolymer containing 55 weight % of methyl acrylate and 2.0 weight % of ethyl hydrogen maleate, the remainder ethylene.
  • ECP-3 an ethylene copolymer containing 23 weight % methyl acrylate, 41 weight % of butyl acrylate and 3.2 weight % of ethyl hydrogen maleate, the remainder ethylene.
  • PVDF a polyvinylidene difluoride available commercially under the tradename Kynar ® HSV900 from Arkema.
  • Al foil is 1 mil aluminum foil from Allfoils.
  • NMP N-Methyl-2-pyrrolidone, commercial grade.
  • IP A isopropyl alcohol commercial grade.
  • Electrolyte Novolyte ® 1M LiPF 6 70-30 EMC-EC.
  • films generated from each polymeric solution were examined under scanning electron microscopy.
  • the films prepared from three different methods exhibited a homogeneously well-mixed appearance even at 100 nm scale magnification.
  • the slurry (i.e., dispersion of cathode active material, carbon black, and binder in a solvent) coated cathode was dried in a convection oven (model FDL-115, Binder Inc., Great River, NY) for an hour while ramping the oven set temperature from 60°C to 120°C.
  • the resulting 51-mm wide cathode was placed between 125- ⁇ thick brass sheets and passed through a calendar three times using 100 mm diameter steel rolls at ambient temperature with nip forces increasing in each of the passes, starting at 1250 psi with the final pass at 1750 psi.
  • An example cathode paste composition was prepared using the materials summarized in Table 1, and it has 13.99 mg NMC/cm 2 of the cathode. Table 1
  • Cathode disks were punched out by using a 0.5-inch diameter arch punch, and were further dried overnight in a dry-box antechamber under vacuum at 90°C. After 18 hours, inside an argon-filled dry box, non-aqueous electrolyte lithium-ion CR2032 coin cells were prepared for electrochemical evaluation.
  • the coin cell parts (case, spacer, wave spring, gasket, and lid) and coin cell crimper were obtained from Hohsen Corp (Osaka, Japan).
  • the anodes were lithium metal (275 ⁇ thick, Chemetall Foote, Kings Mountain, NC) and the separator was a microporous polyolefm (CG2325, Celgard, LLC. Charlotte, NC).
  • the electrolyte was ethyl methyl carbonate (70 v %) /ethylene carbonate (30 v %)/ 1 M LiPF 6 (Novolyte Purolyte ® A2 Series, BASF, Independence, OH).
  • a coin cell with active loading of 13.99 mg NMC/cm 2 was assembled from a blend of PVDF and ECP-1 as in Table 1. Also prepared are a similar cell designated “V” prepared using ECP-1 as a binder and cells designated “Fl” and “F2" prepared using PVDF as a binder.
  • the coin cells were evaluated using a commercial battery tester (Series 4000, Maccor, Tulsa, OK) at ambient temperature and cycling between voltage limits of 3.0 to 4.3 V. First the cells were cycled five times for formation and to determine their initial capacity.
  • Charging was by CC-CV, using a constant current (CC) charge at 28 mA per g of cathode active material to the upper voltage cutoff, followed by a constant voltage (CV) step holding the voltage at the upper limit until the current decayed to 14 mA/g.
  • Discharge was by CC at 28 mA/g.
  • the coulombic efficiency (CE) of each of the five cycles was calculated as
  • CE discharge capacity / charge capacity.
  • a discharge rate test with seven charge-discharge cycles was performed using constant current discharges at 14, 42, 140, 280, 700, 1400, and finally 2800 mA/g.
  • the cells were charged and subjected to a voltage-hold test ("floating voltage” or "leak test") in which the voltage was held constant for 200 hours at ambient temperature at 4.3 V while the current was monitored. The average current in the last 50 hours of the voltage-hold test was 5.4xl0 "7 amp.
  • the cells were again tested for discharge rate capability using the same procedure as above. The capacity in the first and second rate tests, measured at 14 mA/g discharge rate, was compared and used as a measure of capacity loss following the voltage- hold test (first row of Table 3).
  • C-rate is the reciprocal of the time needed to completely discharge or charge a battery, which is typically expressed as the relative discharge current expressed as a multiple of the numeric value of the discharge capacity measured at the lowest discharge rate of 14 mA/g.
  • the cell capacity at the lowest discharge rate was 2.8 mAh
  • 0.1C was a discharge rate of 0.28 mA
  • 1C was a discharge rate of 2.8 mA.
  • Table 4 show four different coin cells based on two different binder systems: a PVDF and an ECP-PVDF hybrid (PVDF modified with30 weight% of ethylene copolymer ECP-1).
  • the cells were prepared using cathode active material of NMC (Lithium Nickel Manganese Cobalt Oxide (LiNio.333Mn 0 .333Coo.3330 2 ) and carbon black (Super C65, Timcal, Westlake, OH) by above described methods.
  • NMC Lithium Nickel Manganese Cobalt Oxide
  • Super C65 Timcal, Westlake, OH
  • the cells of Al, A2, Bl and B2 were cycled using a commercial battery tester (Series 4000, Maccor, Tulsa, OK) at ambient temperature using constant current charging and discharging between voltage limits of 3.0 to 4.25 V at a current of 35 mA per gram of cathode active material (at 0.25 C-rate).
  • the results of testing are summarized in Table 4 (discharge capacity) and Table 5 (coulombic efficiency).
  • a similar cell designated "V" prepared using ECP-1 as a binder. They provided capacity of about 135 mAh/g under 4.25 V charge, 3 V discharge and 0.25 C-rate. Although their discharge capacity is smaller than NMC's theoretical value of 160 mAh/g, possibly due to its 0.25 C-rate, they all performed well by showing stable charge-discharge cycles up to 180 in their half cells, even without optimization.
  • the bending test was done for the electrodes targeted for a thickness of 50 ⁇ . From each formulation, five samples were made in 1-inch by 4-inch size. Each strip of cathode was placed on a stainless steel wire of 1 mm thickness in perpendicular direction at an angle of 180 for the bending test. The area of bent position of the electrode was observed. A test was given a "Pass” rating if no crack was observed for all five samples. "Fail” was used for electrodes that developed any crack and delamination in any of the five samples (Table 7).
  • Flexibility of electrodes was also measured by a three-point flex test that followed ISO 178 with 600 gmf load cell to make force measurements with about 0.3 inch (8 mm) span.
  • Five electrodes were fabricated with the thickness of 177 ⁇ after calendaring.
  • Six samples were prepared from each electrode for the test. The modulus was fit in the linear region of the stress-strain curve and the strain formulas are included in the standard. Average values of modulus, stress and strain of the prepared electrodes are in Table 8.
  • Peel strength of each formulation was obtained based on a modified ASTM D903 method - Standard Test Method for Peel or Stripping Strength of Adhesive Bonds.
  • the thickness of coating for each formulation in Table 6 was adjusted to be 50 ⁇ after drying and calendaring.
  • PSA tape Interpolymer PA-280630, 1 inch wide and 5.0 mil thick
  • PSA taped cathode was placed in a manila folder and passed through a rubber-calendared gap using Fellowes Venus 125 Laminator at room temperature.
  • the rubber-calendared cathode was placed in the nitrogen dry box for minimum 24 hours and maximum 48 hours.
  • PSA taped cathode specimen was mounted by attaching the aluminum current collector side on a steel alignment plate.
  • a double sided PSA tape (Interpolymer SCP-054R, 3.3 mil thick) was used. Peeling was done at a speed of 50 mm/min at 180 ° angle on an Instru-met 1122 testing machine with Instron-made load cell having maximum capacity of 10 pounds and MTS Testworks software. Peel strength of a binder reported in Table 9 is the average value of five specimens between 2 to 5 inch displacements.
  • ECP-modified PVDF binder compared to PVDF alone.
  • the sample with 30 weight % of ECP-l (ECP-PVDF-3) showed adhesion stronger than either PVDF or ECP-l alone.
  • Electrolyte resistance of ECP modified PVDF cathode was tested by blending 30 weight% of ECP resins with PVDF. Three different ECP resins were mixed with PVDF- HSV900 and dissolved in NMP. The prepared resin mixture solution was placed on the FEP container and dried on the convection oven at 120 °C for couple of hours. The dried and thick films were folded and pressed at 150 °C and 1000 pounds for 3 minutes followed by incremental increase of pressure up to 20000 pounds to form a rectangular shape of 0.25 inch, 2 inch and 2 inch size. Prepared blended resin was dried further under house vacuum at 50 °C for overnight.
  • ECP-2 modified 1.334 1.953 1.310 -1.81 1.46

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Polymers & Plastics (AREA)
  • Medicinal Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

Cette invention concerne une composition comprenant un copolymère d'éthylène et un polymère halogéné, le copolymère d'éthyle comprenant ou étant obtenu à partir de motifs répétitifs dérivés de l'éthylène et d'un comonomère choisi dans le groupe constitué par un acide monocarboxylique α,β-insaturé ou son dérivé, un acide dicarboxylique α,β-insaturé ou son dérivé, un monomère contenant un époxyde, un ester de vinyle, ou des combinaisons de deux ou plus d'entre eux ; la composition pouvant comprendre en outre un durcisseur pour réticuler le copolymère d'éthylène. La composition est utile en tant que liant pour une batterie lithium-ion.
PCT/US2014/042026 2013-06-12 2014-06-12 Liant pour batterie hybride à base d'un copolymère d'éthylène-fluoropolymère Ceased WO2014201193A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201361834031P 2013-06-12 2013-06-12
US61/834,031 2013-06-12

Publications (1)

Publication Number Publication Date
WO2014201193A1 true WO2014201193A1 (fr) 2014-12-18

Family

ID=51063872

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2014/042026 Ceased WO2014201193A1 (fr) 2013-06-12 2014-06-12 Liant pour batterie hybride à base d'un copolymère d'éthylène-fluoropolymère

Country Status (2)

Country Link
US (1) US20140370383A1 (fr)
WO (1) WO2014201193A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110556493A (zh) * 2019-08-13 2019-12-10 中国科学院化学研究所 一种锂/钠二次电池功能性复合隔膜及其制备方法
WO2025053606A1 (fr) * 2023-09-05 2025-03-13 주식회사 엘지에너지솔루션 Liant pour électrode positive de batterie entièrement solide, et électrode positive composite et batterie entièrement solide la comprenant

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6184421B2 (ja) 2011-12-21 2017-08-23 ザ リージェンツ オブ ザ ユニバーシティ オブ カリフォルニア 相互接続された波状炭素系網状体
EP2823496B1 (fr) 2012-03-05 2022-10-26 The Regents Of The University Of California Condensateur avec des électrodes faites d'un réseau interconnecté à base de carbone ondulé
US10211495B2 (en) 2014-06-16 2019-02-19 The Regents Of The University Of California Hybrid electrochemical cell
MX2017006315A (es) 2014-11-18 2017-08-21 Univ California Compuesto de red a base de carbono corrugada interconectada (iccn) porosa.
CN104716310A (zh) * 2015-02-11 2015-06-17 深圳新宙邦科技股份有限公司 一种锑/碳复合负极材料及其制备方法
US11069894B2 (en) 2015-12-04 2021-07-20 The University Of Akron Crosslinked polymer binders for electrochemical energy storage devices
IL259749B (en) 2015-12-22 2022-08-01 Univ California Cellular graphene films
KR102645603B1 (ko) 2016-01-22 2024-03-07 더 리전트 오브 더 유니버시티 오브 캘리포니아 고-전압 장치
US11062855B2 (en) 2016-03-23 2021-07-13 The Regents Of The University Of California Devices and methods for high voltage and solar applications
CN105860240B (zh) * 2016-04-25 2018-03-23 江南大学 一种聚偏氟乙烯/乙烯‑丙烯酸丁酯‑甲基丙烯酸缩水甘油酯共聚物合金制备方法
DE102016216252A1 (de) 2016-08-30 2018-03-01 Bayerische Motoren Werke Aktiengesellschaft Elektrode mit verbesserter mechanischer stabilität und galvanisches element enthaltend die elektrode
JP7109790B2 (ja) * 2016-08-31 2022-08-01 ザ リージェンツ オブ ザ ユニバーシティ オブ カリフォルニア 炭素系材料を含むデバイス及びその製造
CA3067725A1 (fr) 2017-07-14 2019-01-17 The Regents Of The University Of California Chemin simple menant de nanopoints de carbone a un graphene poreux hautement conducteur pour applications de supercondensateurs
CN111200132B (zh) * 2018-11-16 2021-05-18 宁德时代新能源科技股份有限公司 一种电池
CN109686981B (zh) * 2018-12-25 2021-03-02 河南电池研究院有限公司 一种应用于锂硫电池的复合粘结剂及其制备方法
KR102771007B1 (ko) * 2020-06-30 2025-02-21 주식회사 엘지에너지솔루션 리튬 이차 전지용 분리막 및 이의 제조방법 및 이에 의해 제조된 분리막
US11404692B1 (en) * 2021-07-23 2022-08-02 Lyten, Inc. Lithium-sulfur battery cathode formed from multiple carbonaceous regions
EP4273968A4 (fr) 2022-01-28 2025-05-21 Contemporary Amperex Technology (Hong Kong) Limited Composition de bouillie d'électrode positive, et feuille d'électrode positive, batterie secondaire, module de batterie, bloc-batterie et dispositif électrique préparés à partir de celle-ci
CN118044001A (zh) * 2022-06-22 2024-05-14 宁德时代新能源科技股份有限公司 粘结剂及其制备方法、正极浆料、正极极片、二次电池、电池模块、电池包和用电装置
CN118930706A (zh) * 2023-05-12 2024-11-12 宁德时代新能源科技股份有限公司 含氟聚合物、导电浆料、负极极片、二次电池和用电装置
CN117327460A (zh) * 2023-12-01 2024-01-02 四川新能源汽车创新中心有限公司 锂离子电池用粘结剂、极片、电解质膜及制备方法
WO2025134134A1 (fr) * 2023-12-20 2025-06-26 Ola Electric Mobility Limited Composition de liant, électrode et procédés associés

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2897183A (en) 1954-01-13 1959-07-28 Du Pont Constant environment process for polymerizing ethylene
US5028674A (en) 1990-06-06 1991-07-02 E. I. Du Pont De Nemours And Company Methanol copolymerization of ethylene
US6680145B2 (en) 2001-08-07 2004-01-20 3M Innovative Properties Company Lithium-ion batteries
US6723785B2 (en) 2000-07-17 2004-04-20 Kao Corporation Process for preparing aqueous dispersion of pigment-containing polymer particles
US6964828B2 (en) 2001-04-27 2005-11-15 3M Innovative Properties Company Cathode compositions for lithium-ion batteries
US7468223B2 (en) 2000-06-22 2008-12-23 Uchicago Argonne, Llc Lithium metal oxide electrodes for lithium cells and batteries
US7718319B2 (en) 2006-09-25 2010-05-18 Board Of Regents, The University Of Texas System Cation-substituted spinel oxide and oxyfluoride cathodes for lithium ion batteries
JP2012109143A (ja) 2010-11-18 2012-06-07 Du Pont Mitsui Fluorochem Co Ltd 電池正極及びリチウムイオン二次電池
WO2012082991A2 (fr) 2010-12-15 2012-06-21 E. I. Du Pont De Nemours And Company Procédé de préparation de dispersions de pigments
US20120264868A1 (en) * 2011-04-14 2012-10-18 Ticona, Llc Reflectors for Light-Emitting Diode Assemblies Containing a White Pigment
JP2012209219A (ja) 2011-03-30 2012-10-25 Sanyo Electric Co Ltd 非水電解質二次電池
JP2012234707A (ja) 2011-04-28 2012-11-29 Unitika Ltd 二次電池電極のバインダー用樹脂組成物、及びこれを用いてなるバインダー液、二次電池電極、二次電池
JP2012238488A (ja) 2011-05-12 2012-12-06 Sumitomo Chemical Co Ltd 電極用バインダー、電極及び該電極を有するリチウムイオン二次電池
WO2013008564A1 (fr) 2011-07-14 2013-01-17 Jsr株式会社 Composition de liant pour électrodes

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2787073B2 (ja) * 1989-10-13 1998-08-13 ジェイエスアール株式会社 ゴム組成物
US5700866A (en) * 1995-08-22 1997-12-23 E. I. Du Pont De Nemours And Company Co-curable base resistant fluoroelastomer blend composition

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2897183A (en) 1954-01-13 1959-07-28 Du Pont Constant environment process for polymerizing ethylene
US5028674A (en) 1990-06-06 1991-07-02 E. I. Du Pont De Nemours And Company Methanol copolymerization of ethylene
US7468223B2 (en) 2000-06-22 2008-12-23 Uchicago Argonne, Llc Lithium metal oxide electrodes for lithium cells and batteries
US6723785B2 (en) 2000-07-17 2004-04-20 Kao Corporation Process for preparing aqueous dispersion of pigment-containing polymer particles
US6964828B2 (en) 2001-04-27 2005-11-15 3M Innovative Properties Company Cathode compositions for lithium-ion batteries
US7078128B2 (en) 2001-04-27 2006-07-18 3M Innovative Properties Company Cathode compositions for lithium-ion batteries
US6680145B2 (en) 2001-08-07 2004-01-20 3M Innovative Properties Company Lithium-ion batteries
US7718319B2 (en) 2006-09-25 2010-05-18 Board Of Regents, The University Of Texas System Cation-substituted spinel oxide and oxyfluoride cathodes for lithium ion batteries
JP2012109143A (ja) 2010-11-18 2012-06-07 Du Pont Mitsui Fluorochem Co Ltd 電池正極及びリチウムイオン二次電池
WO2012082991A2 (fr) 2010-12-15 2012-06-21 E. I. Du Pont De Nemours And Company Procédé de préparation de dispersions de pigments
JP2012209219A (ja) 2011-03-30 2012-10-25 Sanyo Electric Co Ltd 非水電解質二次電池
US20120264868A1 (en) * 2011-04-14 2012-10-18 Ticona, Llc Reflectors for Light-Emitting Diode Assemblies Containing a White Pigment
JP2012234707A (ja) 2011-04-28 2012-11-29 Unitika Ltd 二次電池電極のバインダー用樹脂組成物、及びこれを用いてなるバインダー液、二次電池電極、二次電池
JP2012238488A (ja) 2011-05-12 2012-12-06 Sumitomo Chemical Co Ltd 電極用バインダー、電極及び該電極を有するリチウムイオン二次電池
WO2013008564A1 (fr) 2011-07-14 2013-01-17 Jsr株式会社 Composition de liant pour électrodes

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SPERLING, L. H.: "Interpenetrating polymer networks; Klempner, D., et. al.; Advances in Chemistry", 1994, AMERICAN CHEMICAL SOCIETY, article "Interpenetrating Polymer Networks: An Overview"

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110556493A (zh) * 2019-08-13 2019-12-10 中国科学院化学研究所 一种锂/钠二次电池功能性复合隔膜及其制备方法
CN110556493B (zh) * 2019-08-13 2021-04-27 中国科学院化学研究所 一种锂/钠二次电池功能性复合隔膜及其制备方法
WO2025053606A1 (fr) * 2023-09-05 2025-03-13 주식회사 엘지에너지솔루션 Liant pour électrode positive de batterie entièrement solide, et électrode positive composite et batterie entièrement solide la comprenant
EP4586343A4 (fr) * 2023-09-05 2026-04-29 Lg Energy Solution Ltd Liant pour électrode positive de batterie entièrement solide, et électrode positive composite et batterie entièrement solide la comprenant

Also Published As

Publication number Publication date
US20140370383A1 (en) 2014-12-18

Similar Documents

Publication Publication Date Title
US20140370383A1 (en) Ethylene copolymer-fluoropolymer hybrid battery binder
WO2014201194A1 (fr) Liant de batterie hybride
US11404697B2 (en) Solid electrolyte interphase forming composition, battery comprising the solid electrolyte interphase and anode-free battery comprising the solid electrolyte interphase
KR101625348B1 (ko) 리튬 이차 전지의 정극 합제용 슬러리, 상기 슬러리를 사용한 정극 및 리튬 이차 전지
US9564639B2 (en) High performance silicon electrodes having improved interfacial adhesion between binder and silicon
CN114144932A (zh) 一种隔离膜及包含所述隔离膜的电化学装置和电子装置
JP5168989B2 (ja) リチウムイオン二次電池
US20140312268A1 (en) Battery binder
WO2011096564A1 (fr) Film composite d'électrolyte en gel pour batterie secondaire et batterie secondaire
CN102318108A (zh) 锂二次电池的电极合剂用浆料、使用了该浆料的电极和锂二次电池
CN102473916A (zh) 锂二次电池的电极合剂用浆料、使用了该浆料的电极和锂二次电池
US12555794B2 (en) Electrochemical apparatus and electronic apparatus
JP2014063676A (ja) 二次電池正極用水系バインダー液、およびこれを用いてなる二次電池正極用水系ペースト、二次電池正極、二次電池
CN107785578A (zh) 正极添加剂及其制备方法、正极片及锂离子二次电池
JP2014132591A (ja) リチウム二次電池の電極合剤用スラリー、電極、その製造方法およびリチウム二次電池
US20150280278A1 (en) Amorphous polyamide derived from aromatic dicarboxylic acid as a binder for lithium ion battery electrode
US20140312282A1 (en) Battery binder
CN118120089A (zh) 一种二次电池和电子装置
JP2004356004A (ja) 正極板およびそれを含む非水電解質二次電池
KR101323269B1 (ko) 고온 특성 향상을 위한 전극용 바인더 조성물 및 이를 포함하는 리튬이차전지
CN101263167A (zh) 用于电池电极的乙烯基氟基共聚物粘合剂
WO2015175276A1 (fr) Compositions d'électrode et dispositifs de stockage d'énergie
JP5697906B2 (ja) 二次電池用電極水系組成物
US6727019B2 (en) Electrochemical cell having an ionomer binder of Li-AMPS and associated fabrication
JP5509644B2 (ja) リチウム二次電池の電極合剤用スラリー、電極、その製造方法およびリチウム二次電池

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14735808

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 14735808

Country of ref document: EP

Kind code of ref document: A1